1. Field of the Invention
The present invention relates to a device for epicardial support and/or the assuming of cardiac activity having a double membrane consisting of an elastic inner membrane and a non-expandable outer membrane as well as a closed cavity formed therebetween which can be inflated and deflated by means of a fluid exhibiting a first chamber allocated to the right ventricle and a second chamber allocated to the left ventricle.
2. Description of Related Art
Such a device—although one which works pericardially—is known for example from the document DE 199 51 220 A1. The device is a minimally-invasive, i.e. percutaneously implantable system for the mechanical support and temporary substitution of the heart's pumping function. After probing the pericardial sac, the device is inserted into the pericardial sac percutaneously in collapsed state or surgically positioned in the pericardial sac at the end of an operation with the double membrane surrounding the right and left ventricles. The device in its deflated state is so thin that a compression of the adjacent organs will be avoided. Subsequent implantation, the cavity of the double membrane is rhythmically supplied through a connecting tube with a fluid which can either be a gas (helium or CO2) or a suitable liquid. Due to this rhythmic inflation and deflation of the double membrane's cavity and because the outer membrane is not expandable in contrast to the inner membrane, the double membrane surrounding the heart effects pressure transmission and compression of the heart. In so doing, blood is urged from the right ventricle into the pulmonary artery and simultaneously from the left ventricle into the aorta or, when the heart is pumping, aids in the systolic ejection of the cardiac muscle.
A device for supporting cardiac activity is known from U.S. Pat. No. 5,169,381 A which has a double membrane comprising an inner and an outer membrane as well as a closed cavity formed therebetween which can be inflated and deflated by means of a fluid. This double membrane has an axially-extending wedge-shaped slot spanning ¾ of the vertical extension of the double membrane and is furthermore provided with a first chamber allocated to the right ventricle and a second chamber allocated to the left ventricle. Each of these two chambers are supplied with fluid separately, which entails a double expenditure of fluid tubes and valves and results in the device as a whole being relatively complicated in its operation.
Against the background of the disadvantages of the latter device for supporting cardiac activity as described, the task on which the present invention is based is that of providing simple operability of the device while maintaining the advantage of being able to augment only one ventricle.